Aerosolization of colloidal nanoparticles by a residual-free atomizer

Abstract A new residual-free atomizer was designed to transfer colloidal nanoparticles measuring less than 100 nm into aerosol phase. Miniaturization of droplet size distribution successfully reduced background aerosol concentration of particles sized greater than 2.5 nm to 400 particles·mL−1 of gas, which corresponded to an NaCl-equivalent impurity concentration of less than 100 ppb. Direct injection of colloid suspension enabled precise control of aerosol number concentrations by colloidal concentration (105–1011 particles·mL−1 of liquid). Correlations between the size distributions of colloid and aerosol were also investigated using aqueous suspensions of the standard nanoparticles sized 10–100 nm. It was found that the aerosol size distribution was in very good agreement (i.e., less than 1 nm accuracy) with that measured by scanning electron microscopy. Copyright © 2020 American Association for Aerosol Research